Field of the Invention
The present invention relates in general to data storage, more particularly, to deduplicating data for storage and accessing deduplicated data from the storage.
Description of the Related Art
Computing environments increasingly store data in one or more storage environments, which in many cases are remote from the local interface presented to a user. These computing storage environments may use many storage devices such as disk drives, often working in concert, to store, retrieve, and update a large body of data, which may then be provided to a host computer requesting or sending the data. In some cases, a number of data storage subsystems are collectively managed as a single data storage system. These subsystems may be managed by host “sysplex” (system complex) configurations that combine several processing units or clusters of processing units. In this way, multi-tiered/multi-system computing environments, often including a variety of types of storage devices, may be used to organize and process large quantities of data.
Some storage devices used in the computing environments employ magnetic hard disks. Magnetic hard disks include a disk spindle for holding flat disk platters. Information is written to and/or read from a disk platter as the platter rotates. In particular, an actuator arm moves read-and-write heads on an arc across the platters as they spin to allow each head to access almost an entire surface of the platter. The heads access annular tracks on the platters, which are numbered from an outermost track inward. Each track is divided into sectors to store a fixed amount of data. To manage file storage, file blocks are mapped to logical block units, and the logical block units are mapped to physical blocks on the magnetic hard disks. In this way, file management is maintained independent of storage management.